Tony D

I would say the fueling is actually over-rich past your torque peak. We lost major power running anything richer than 12.5 almost every point past torque peak. From talking to people in general who have dynoed their cars and noted the changes, it seems that you need to actually pull fuel past torque peak. For instance, on JeffP's car we started at something around 11:1 across the board, we started experimenting pulling fuel at various points watching EGT's as well. Some people said they tuned to 1650F, we didn't get anywhere near that point, but were amazed at higher rpms (with porting and a cam) that in some load bins we were actually running as lean at 13.8!!! Most of the stuff was in the high 12's, which was FAR LEANER than anything before torque peak. I encapsulate this in a short synopsis, it took FAR longer on the dyno than we thought before we realized that running the same AFR past torque peak was actually too rich, and we were loosing considerable power. Just make sure their datalogging equipment is calibrated properly, and stick with the same place to (as noted above) monitor relative changes from your adjustments.

To address in turn: 1) You are confusing puking coolant with nucleate boiling. If you aren't puking coolant with a 16 psi cap, it does not mean that you aren't nucleate boiling. You may not be, but because it doesn't get to that point doesn't mean it isn't happening. the higher pressure cap gives nucleate boiling margin just as an oversized radiator core does for normal operating temperature. THEY ARE SEPARATE ISSUES. That you have cooling margin is one thing. The largest radiator and pump in the world will give you tons of margin for cooling. Simple cooling. But PRESSURE is what actually CHANGES THE POINT AT WHERE IT BOILS. Because it's operating at a higher pressure, the chance that nucleate boiling will occur, and go runaway is FARTHER away than with the 16 psi cap. 2) My contention (politely) will be that you dont, follow to point 3 and you should see why. 3) Detonation (or tendency to detonate) due to inadequate cooling of the cylinder head caused by nucleate boiling will be reduced by running the higher pressure cap, because of the margin of increase you get by that increased pressure. Instead of nucleate boiling at 230, now it's 265 (JeffP has recorded this temperature in his engine, BTW!) If you are running a 160 thermostat, it does not mean that everywhere in the engine is 160F! The higher pressure cap will save you from the runaway should conditions get to that point. If your system has capacity in excess, the higher pressure cap on the surface will not benefit you, but the MARGIN it will add if anything ABNORMAL occurs between turns 3 and 4, (two miles from the pits) that you will experience LESS of a problem than you would with a stnadard 16psi cap. Again, you mention 'without venting' and that is an IRRELEVANT item when dealing with nucleate boiling. It does not necessarily happen that it gets hot enough to make ENOUGH steam to cause a venting incident. You CAN be nucleate boiling, and not have a venting issue. My example of pukeover after shutdown was intended to show an EXTREME case of boiling (due to no coolant flow from the PUMP...) The PUMP ADDS PRESSURE in the engine ABOVE the CAP. CAP pressure only matters after shutdown for venting issues. If you are venting during running, you are nucleate boiling (outside of normal thermal expansion of volume of the coolant). If you are not venting, it is not proof that you are not nucleate boiling at portions of your head. For Electramotive, we were told the pressures run in their coolant system were in excess of 2 bar static blanket, and they had modified certian aspects of the cooling system to allow a 300% increase in flow through the engine in order to insure no coolant related issues on their turbo car. Frankly, for an N/A car, this may be hard to understand or justify at a specific output of only 100HP per liter or less. When you are talking about 250 or 330HP per liter, on this engine, with this head and combustion chamber design.... it becomes more clear you aren't in Kansas any more Toto!

Carburetor Shop in Ontario California once told me to try Vanish Toilet Bowl Cleaner. It's caustic and won't eat the Mazak or other metals but if you leave it in there too long it WILL turn it jet black. I would make up a pot (stainless steel food service trays I had laying around) and it seemed pretty good with some goggles, tooth brushes, and latex gloves at getting most of the stuff knocked out to where things like frozen throttle plates and shafts would free up. I limited my soaking/working time in the relatively strong solution to around 10 minutes, then completely flushed them with water. Then back to PB Blaster, heat, etc.... If no luck, back in for another 10 minutes of work and then reflush with water and try the oils again. Heating the stuff to around 140 F seemed to make the action much more agressive. I wouldn't use acid as it WILL deteriorate the metal. Likely all you have is corrosion or debris sticking them---and chokes can be oil fouled, meaning an alkaline solution will remove the oils leaving only dirt remaining...and the brushes will get that! Good Luck.

Protection from lawsuits is required these days. Piper Aviation is a good example... Lawyers have no bounds unless reeled in, and even then for over 2000 years the answer has been known... I don't know the phrase in Latin, but it was translated as: "First, Kill all the Lawyers"

It is a common wire, and the added resistance in the line acts as a 'check valve' during some periods of operation. I removed mine, reinstalled, and eventually removed it to no difference in operation of my Autometer Tach. Mine now resides in the glove box...

One thing to note was that the ABC Expose was talking about expired/aged tires being sold 'as new' which IS a problem. There are now 'recall' requirements for tires. The Braap post on his motorhome has a post in it from John Coffee about changing his tires on his trailer. That was a direct result of me revealing that at least one of the tires on MY newly-bought trailer could have possibly been as old as 1978! Some of the tires were old enough to NOT have the UTQG Dating information on them putting them into the mid 80's (and they were replacements!) Old tires are out there, they can kill you. Don't be stupid. As far as making comments about people driving 35 year old tires as being insane... There are some who would say that a tire kept in indoor storage, with no checking, 100% tread, and some of the original molding nipples on it would pose no hazard whatsoever being driven below 50mph. I'm not saying it was right, but the tire looked as good as any tire on the shelf at the dealership. The assumption was with less than 15K on it, 'how bad could it be'? Not such an insane bit of logic. Stupid, but I can see the person's thinking. Were someone to have bought the car, devoid of date coding on the tire, there was no way to tell HOW old the cars tires were! They may have only been 15 years old. (actually at that point, less than 10 years as I believe the datecoding was implemented in the mid 80's and this was in the mid 90's). The bottom line is 'no matter how good it LOOKS, it can fail catastrophically-and that means new tires as well: DRIVE ACCORDINGLY!' For those of us old enough to remember when NEW TIRE BLOWOUTS were a common occurance...

(Sigh) Ok, then the one that came apart in chunks after 4 years is in no way applicable. What's extreme about 4 years? Ozone attack in the southwest will kill a tire FAR quicker than most other places. To put out a statement that 'extreme' conditions are required to make a tire fail is foolish. I have seen NEW tires fail. (Let's not get into Explorer discussions, I'm not even going there...) The Federal Government has required the 6-7 year limit due to the failures of the Explorer, and the precipitant litigation. They had to pick an 'idiot limit' where they could be sure most people would have already changed them. Note they specifically state in the guidelines now that it includes spare tires which have never been used. IMO if you are running 6 year old tires on anything you're an idiot. But then again, that's just me. I would not say 'hey, if you aren't driving them the the extreme they're fine for X years" I do have older tires on my vehicles, I call them 'pushing around the yard rollers'. They are usually what goes on a car when it goes to the paint shop. Nothing I'm regularly driving usually has a tire on it more than a year old, much less two or three. Anything over three is trash for me, regardless of 'tread left'... I usually rotate the spare, but if it just sits it's relegated to 'pushing status' after a few cycles of new tires on the car.

You need to go to the grapeaperacing site and read the information on cooling there, this will make it crystal clear why spot boiling will cause a runaway thermal situation in an engine. Steam is an insulator, and once the steam blankets the head from spot boiling, it can't transfer heat, and then it all goes to hell. By raising the boiling point through pressure, you decrease the tendency to spot boil. Look who is having problems: people with 160 degree thermostats running 20psi caps! If it's happening there, what do you think is happening with 190 thermostats? Because you have 'steam' it doesn't mean 'boilover'---it can go back into solution as it hits cooler water. You will never know it! I got into a debate with someone here about radiator cap pressures because they contended c ap pressure was the same as block pressure. The only people who say that are people who have never run a water pressure gauge on their engine...it's a foolish contention to make. You have close to 40psi in your block with a 16psi cap and the engine at speed. With a higher pressure cap, the NPSH on the pump is higher, and your output pressure is higher. When you realize this is the conditions below the restrictor plate/thermostat, you can start to see exactly how hot some of the head pockets are getting! Anybody but me ever jig up a thermostat housing with a thermostat in it and start applying pressure to see at what point the thermostat acts as a 'relief valve' and lifts off it's seat? Once you do that, after you have witnessed for youreslf what pressures exist in the block at speed with a conventional 1 bar rad cap, you will realize why restrictor plates are run, and why they run a 30 psi cap+ on racing L's making 1000 hp. Some of the information in the "How To Modify" book was altered to the expected audience, or because of someone's understanding of why things are done the way they are... but may not necessarily be true. I mean, if a thermostat lifts at 50 or 60 psi anyway, why bother with it at all and simply put in a flow restricting orifice which will do the same thing and doesn't have the possibility of failing or having a variable flow rate dependent on engine speed (and consequently block pressure)? As for comments about ambient temperature, you are off the mark somewhat. I have personally recorded a 25C day where the engine was operating in a more severe environment than a 40C day elsewhere on the same continent. What is important is macadam thermal layering. This is the temperature your RADIATOR encounters on any given day. It may be 40 and overcast, no problems. 40 and clear and you overheat. Because the thermal radiation warming the macadam surface of the roadway up to 1M from the surface can be considerably hotter than ambient. I have seen (I regress to Farenheit for my own specific clarity) 85 Ambient but 130 through the radiator in Southern CA climbing hte Baker Grade and had to slow to 65mph to keep the car from surging (and engine temperatures at 195+), and three days later in Iowa was going 110mph at 103F ambient, with a 105 thermal layer on a clear day (engine temperature no more than 170), but with the midwestern aerosols blocking UV radiation on the roadway. Yes, on some of my trips, I has 100ohm Platinum RTD's and J/K thermocouples taped and wired all over my car, and my kid was writing down numbers as I drove (kept the kid busy... on the return trip from Canada, this 8 year old decided to read Beowulf...) On this particular trip, based on previous long trip experience I brought along 8liters of premix to add to the radiator for the 'shutdown puke' that occurs on the cars after you shut them down hot after a long highway run. The previous summer I puked 4L over a 1500 mile round trip. I assumed it would be similar with similar conditions. One variable had changed: Water Wetter. On this longer trip, I had the coolant in the same ratios, the same thermostat (160F) in the same car, with the same radiator, blah blah blah. KTM has seen 'The Blue Turd' and can attest firsthand that not much changes on that car year to year (or decade to decade!) On my trip to Canada I did not loose ONE liter over the course of three weeks driving and close to 18,000 miles. The decreased surface tension caused by the water wetter completely STOPPED the 'pops and crackles' I could hear within the head after shutdown. It stopped pressure rise to the cap venting point. If you run in hot weather, run a 160 thermostat, and water wetter. I've done so in my Fairlady Z with a recovery tank, and though thermal expansion may occur, in many years of driving I've not lost nor had to add anything to that car either. The Turd does not puke after shutdown like it did before WW. Run a 190 thermostat, and sure as hell you will puke! Even with water wetter. If someone wants to do the theermodynamic calculations to justify the adibiatic advantages of running the hotter water temperature and put them out there for everyone to see, be my guest. But this requirement that we run these 190 thermostats (which in Nissan Manuals is called for ONLY in "FRIGID" climates) is purely based on theoretical bunk... there is a marginal aadvantage but in practical terms the headaches you encounter make it not worth the effort. Your oil gets to the required 180F with a 160 thermostat (the coldest recommended by Nissan---for 'tropical' climates, curious how it works like that, huh?) and will run hotter depending on load. "So my question is if the conditions never cause the 13 psi cap to vent, how would putting a higher pressure cap on reduce spot boiling in the head? " Hopefully above has told you why. To put it more succintly and without the long read: Higher Pressures in the block will RAISE THE BOILING POINT (and this decreases the tendency to boil...right?) The higher pressure cap IS NOT TO PREVENT VENTING it is there to raise the boiling point so it doesn't spot boil, and then insulate everything---read the grapeaperacing page! I digress...time to go to lunch anyway.

Holy Necroposting Spooner Batman! Depending on your routing of the hoses on the heater circuit, you could effectively block a very nicely designed thermal siphon effect not running them the way I suggest. After shutdown, the routing I suggested has the hot turbo with cool water available at the pump inlet. The turbo heats that water hotter than engine heat, and it rises to the thermostat housing where it can discharge through the open thermostat into the radiator hose. Going heater hose to heater hose will give you no place for the heated water to RISE to without restriction, and it will also have to fight hydrostatic head of the water in the block to return. Thermal siphons are very delicate balances, and don't tolerate much before they stop. AFTER the shutdown is the most critical cooldown time, I'd err on the side of the system that gave me automatic circulation when the engine is OFF. That Nissan used this same routing is no coincidence. Their engineers do sometimes know what they are doing!

I might be interested in it for my 1200cc VW engine...

Built early/mid 80's. I saw it in 1988 or 89. I've got it in some Carboys of that period I believe.

The assumption the carb bowls have not boiled out dry is a bad one to make, even in frigid climates. Winter gas will prove extrememly volatile and can 'boil out' same as in the desert southwest if you have an unseasonably warm day (say it gets up to 30 when normally it's -10 outside and fourmulations take this into account). My 71-Carbed 260Z will take extended cranking to refill the bowls with CA premium if I have a hot shutdown and leave it sit overnight. UNLESS I flick my little e-pump switch and prime the bowls. I use a facet pump inline up in the engine bay. I also use this pump when the car has been sitting at the airport for over a month. If I prime the bowls and engage the starter system on the carbs (unless you got flat tops, it's NOT a 'choke'!) the car will fire off immediately. If not primed, much cranking is required to reprime the bowls. As for Gear Reduction, the primary reason for installation on the ZX's was to keep system voltage higher so they didn't fry the ECU during cranking. If the battery drops to below 9V, some of the early ECUs would poof! Putting them on earlier cars won't do much for you (and in some instances they are actually HEAVIER than the starters they replace!!! So much for blanket statements...) other than stabilize system voltage during extended cranking. If your float bowls are dry, a priming pump (like OEM installed on later cars, and had from the factory since day ONE in some markets for the 240) is the way to go. With a primed bowl and the starter system engaged, it should fire off pretty quickly. Running a transistor pump for 20 seconds is FAR less taxing on the battery than turning ANY starter to fill a float bowl by turning the engine over and running the mechanical pump. The little ticking Facet pump will blow fuel right through the stock (or replacment) mechanical pump, and fill those bowls no problem, then simply stop pushing fuel once it's pressure limit is reached (around 3psi...) Determine the cause, then go after it. Throwing parts will be expensive and may not solve your issue. But I put that primer pump on my car, and it's saved me with a nearly dead battery at the airport more than once! During the summer if it sits, that fuel goes away, period. The only way to fill it is cranking, or an e-pump.

Like driving on the freeway at 50 mph on a straight level roadway with no ruts? Being driven to a concours... Which was about all the driving it got. That was the condition the show-winning 'all original' 260Z was running when it's left rear wheel catastrophically failed and took out the quarter panel. Less than 15K on the tires. They had to still be good. Tires are tires, they only gots 15K on them.... Old tires are dangerous. How many times a year do you go to vegas determines how old you will permit them to be and still drive on them...

Check your CHT or CTS---if the engine temperature sensor is loose or off altogether, it will do this. Any return line on a 260 or later will work fine with the ZXT fuel pump. Only the 240Z with it's 3/16" line will prove to be a problem at idle due to insufficient flow capability. My bet is your engine temperature sensor is loose...

That's a cut down stocker if I ever saw one! What's it weigh, about 15#?

mmmm ginger fish sauce.....gaaaaarrrrrgh!

At 173.325+ mph at Bonneville, the Land Speed Z is a "one-handed-ride" We do not have the 'hood vents' discussed, nor do we have an Air Dam... El Mirage, with talcum-powder dirt exposed between hardpack is more demanding... you can check those runs out on You-Tube: "9500 RPM Shiftpoints" or "Bad Day at El Mirage"

I have an old Nomograph on a Bosch Dyno Sheet from when I was in Japan and dynoed my bone-stock L20A powered Fairlady Z (97PS)... They actually read KW, and then converted to PS. I was going to dig it up, but someone beat me to it! And the 600PS Blue S30 was from SSS (Speed Shop Sinohara) most likely, and it is the original "Devil Z" of the Wangan Midnight Series. Yes, it can be. I've seen the car in person. Well, it was... don't know if it still 'is'...

Ooooh! That's more than price competitive/comparable with Mr. Pollard up in Goleta... Now if I hadn't just bought that Hillborn Setup... Well, time to milk some more overtime I guess!

"Also, I doubt anyone here would pull a head to replace a gasket on a car with 92k/192k (take your pick) and not have it surfaced , at least I would not. " I think me an Blue Destiny are two that won'tresurface a head unless there is a REASON to do it. Channeling, warpage, something. I pulled my head at 243,000 miles because I was SURE the 3/4 cylinder fire rings had blown and either the head or the block had channelled (by compression test alone 150, 150, 100, 100, 150, 150)... Pulled head, NO channelling, nothing. Lapped the valves, and found they were not well seated. Drove the car 18,000 miles in the next three weeks (from SoCal to Kingston Ontario Canada, Boston, around most of the PNW, and the Great Lakes Circly Route)---no resurface of the head whatsoever. Matter of fact, LAST WEEK I finally pulled the intake-exhaust gasket (FelPro Rectangular Gasket on a Roundport N47 head with the Rectangular Port Stock Exhaust Manifold on it) now 10+ years later after no issues whatsoever. Pulled it because the MSA collector flanges caught on something, jerked the exhaust, and broke the manifold... Now it has a round port header which I will never use on anything else once that E88 gets here from Mr. Shewbrook....... But I digress. Because it's off does NOT mean it needs surfacing! Doing maintenance for maintenance's sake just wastes your time and your money. Like BD and Braap mention, there ARE instances were it may be called for, and then it's due more than just a simple decking on one side....likely you are better finding another example in that case. The heads surfaced start getting less and less serviceable. Shims only go so far. Eventually you end up with a head that can't be shaved at all any further. The economics of just letting it run and replacing it are hard to beat compared to 'interim' repairs.

Er... yeah! Some people are hard headed and don't get the hint... and it takes them longer to realize they should leave...(cough!)

Er.... No difference other than the size of the door side impact beam you mean... right? Everything else is minor (mirror mounting on GL's with electric mirrors---big holes that need to be filled on the skin, etc...)

Hmmmmmmmmmmmmm Now I have to make an inquiry before restoring the four-spoke Cragar SS's I have...

RON is RON, but the pump rating may be RON, MON, or R+M/2 as in most of the USA. The standard in USA is R+M/2. Outside the USA depending on where you are, it could be any of the above combinations. MON is really the most important as it's a physical check of the fuel in an actual knock engine. Honda used a fuel in F1 during the turbo years that met the MON standard of 104 or whatever it was at the time, but it's RON was close to 70! Exotic blend, but it ran great as long as charge temperature was above 140F...so it would atomize. It wouldn't run your street car... but in the USA if sold for motor fuel it would have had a rating of 104+70/2 = 86 or basically 'regular'... It's actual performance was equivalent to 104 when run in the engine as the engine was designed around the fuel...

Good Point on Circuit Breaker Sizing and Availability. When I sited my place, I asked for the largest Residential Service I could get (250Amps to the Meter) and they about choked. "Your's is not to question why Mr. Contractor, yours is to give me what the hell I want!" Down the road, with 50 amps to the house doing fine, a 30 and 50Amp circuit to my sheds behind the house... I still have plenty of power to play with... The CyberTig is multi-voltage and is a 100Amp draw. Too much for my dryer circuit, to be sure! (Which would make the house draw 100Amps total on the circuit.) As you stated actually USING 240V appliances make the E-Bill go up quickly. Which is my impetus for keeping in Pete's good graces and my bid firmly in for his Kholer Powered Bobcat. I felt his Kaiser Jeep powered Lincoln Trailblazer was just a bit much... As for moving the CyberTig, it was a bit more than 500#, and I used a 1-ton gantry I have at the house to lift it off since my forklift didn't have long enough forks. It's movement was restricted originally to a 10X14 pad of concrete I had between my sheds. Now with more concrete I can move it about more and more on it's roller cart (which holds two tanks, and the coolant pump as well as cooling fluid for the torch head.) Most of this stuff can be moved in a pickup truck, getting it off and placed can be an issue but a 4 hour rental of equipment may be needed to do it easily. Once it's down, likely it won't be moved for another 20 years...